How to find existence of many-to-many children records that meet a criteria?

[nelsonjd]

I'm trying to find existence of certain Permissions on a single parent Role (many-to-many).

const roles = await Role
  .query()
  .preload('permissions')

this.role = roles.find(role => role.id === someid)

const exists = this.role.permissions.some(permission => permission.name === 'something')

This is the solution so far, which seems not optimal.
Is there a way to do this without loading all the roles and permissions and looping through them in Javascript?
Thank you so much 🙏

[thetutlage]

If I get it right, you want to find if a role with a specific id has a given permission or not. If yes, you can use the following query.

const matchingRole = await Role.query().where('id', someId).whereHas('permissions', (subquery) => {
  subquery.where('name', 'something')
}).first()

if (!matchingRole) {
  // no match found
}